How to get the current time in milliseconds from C in Linux?

Question

How do I get the current time on Linux in milliseconds?

Answer 1

Derived from Dan Moulding's POSIX answer, this should work :

#include 
#include 

long millis(){
    struct timespec _t;
    clock_gettime(CLOCK_REALTIME, &_t);
    return _t.tv_sec*1000 + lround(_t.tv_nsec/1.0e6);
}

Also as pointed out by David Guyon: compile with -lm